Apparatus for removing air from ceramic materials



C. O. FIEDLER Feb. 17, 1953 APPARATUS FOR REMOVING AIR FROM CERAMIC MATERIALS SHEETS-SHEET 1 Filed Jan. 22. .`|.952

lll

|NVENT0R CLIFFORD 0. FIEDLER ATTORNEYS Feb. 17, 1953 c. o. FIEDLER 2,628,401

APPARATUS FOR REMOVING AIR FROM CERAMIC MATERIALS I Filed Jan. 22. 1952 SHEETS- SHEET 2 R rr. L D Rrr. mr. N E0 V N ID Dn 0 Ll .r l. c

BY Z

ATTORNEYS Patented Feb. 17, 1953 UNITED STATES FTNT 1OFFICE APPARATUS FOR REMOVING AIR FROM CERAMIC MATEREALS Clifford O. Fiedler, San Gabriel, Calif.

Application `lanuary 22, 1952, Serial No. 267,641

4 Claims. (Cl. 2511) from, since if the clays are not nely and evenly comminuted and if they contain air or gas, the quality of thecrnolded product is poor. In the preparation of such clays, it has been customary, during the comminutng or mixing operation, to pass them through a Vacuum chamber for the purpose of removing air and gases, but since the Vacuum chamber must of course be maintained sealed from atmosphere, certain difliculties have been presented. For instance inasmuch as the clays must pass into and out of the chamber considerable diiiiculty has been experienced in maintaining the necessary plug of impacted material at the inlet to effectively maintain the chamber sealed from atmosphere. While the consi-stencies of some clays have rendered it easy to maintain such a seal, the consistencies of other clays have rendered it practically impossible to maintain an effective seal.

It is therefore an object of my invention to provide an apparatus of this character wherein I overcome this old problem by providing a construction by which it is possible to adjust the size of the extrusion orices in the wall of the vacuum chamber at the point at which the shaft carrying the comminuting blades passes through the wall.

It is also an object to provide apparatus in which, by virtue of its construction, I am able to arrange all the parts in linear relation so that the machine is more compact and efficient.

Other objects and advantages will appear hereinafter.

Without intending thereby to limit the broader scope of the invention, except as may appear from the appended claims, I shall now describe a presently preferred apparatus embodying my invention, for which purpose I shall refer to the accompanying drawings wherein:

Fig. l is a View partly in side elevation and partly in longitudinal section;

Fig. 2 is a section taken on line 2 2 of l;

Fig. 3 is an enlarged section taken on line 3 3 of Fig. l;

Fig. 4 is a section taken on line iA-l of Fig. 3;

Fig. 5 is a top plan view of Fig. 1;

6 is an enlarged section taken on line fi-t of Fig. 1;

Fig. 7 is a section taken on line l--l of Fig. 6;

Fig. 8 is a sectional View showing the mounting of the comminuting blades upon the shaft; and

Fig. 9 is a perspective of one of the comminuting blades.

Referring now to the accompanying drawings: The numeral 5 denotes an open topped casing supported upon a base 1.

The casing has a right end wall 9 and a left end wall lll providing journals I5, I6 for shaft 2@ which carries comminuting blades 2l of the l" pug mill type, pitched to advance the clay longitudinally of the casing towards end wall i0. Shaft 2D is driven as by a motor M through conventional chain and sprockets 23.

The raw clay or other plastic material to be prepared is fed into the right hand end of the casing through a conduit 24 from a conventional hopper, not shown. Adjacent wall I0 shaft 20 carries a helical screw 25, so that when the shaft is rotated a plug of the material is maintained in the cylindrical plug chamber 26 against wall lll.

Walls 29, 30 and 3|, together with wall l0, dene a vacuum chamber 32, from which air is evacuated through an outlet opening 33 by means of a Vacuum pump, not shown. Top wall 29 of the chamber is provided with inspection openings 35 having cover glasses 35 in sealing engagement therewith.

An extension portion 20a of the shaft, which is preferably although not necessarily of reduced diameter, extends through chamber 32 and carries comminuting blades 2| a, the shaft portion 2da being journaled at its left end in a, spider 38 mounted at the discharge end of a reduced cylindrical portion 39 of the vacuum chamber, the left end portion of the shaft carrying a helical screw dll which maintains a plug of material within the conical extrusion nozzle 42.

While, with some materials it is relatively easy to maintain a suitable plug seal of the material in chamber 25 against wall l0; with other materials it is dincult. .So as to enable my apparatus thereby to handle materials of all types, I provide an adjustable extrusion member in association with wall l0 of the vacuum chamber and which will now be described.

Wall itl has, radially spaced from the shaft, a circumferential row of extrusion orifices 5l), and against wall iii, and coaxial with the shaft, I rotatably mount a disc 52, also having a circumferential row of extrusion orifices arranged to be moved into and out of register with orifices 5t upon rotation of the disc relative to wall it.

To mount disc 52, I secure a ring 5l to Wall IIJ, as by screws '58, the rings having an inwardly disposed annular flange 59 which bears against the outer surface of the disc adjacent the periphery of the latter, so that the disc may rotate in the ring. A collar consisting of sections Eli-6I, secured together by screws 63 rotat-ably fits around shaft portion 26a and is locked to disc 52 by pins 65a.

To rotate the disc 52, it is provided with a bifurcated radial varm 65. Througha side wall of the chamber 32 a tubular housing 261 extends. The housing has a right end wall 6B and the left end carries a screw plug 69. Operating shaft 10 is threadedly mounted in plug 69 and extends through said plug and through wa1l'68, carrying an annulus 12 adjacent its outer end, which engages between the bifurcations of arm 65, so as to swing the arm 65 in response to rotation of shaft '10. The other end of the shaft carries a hand wheel 12 for manual operation. The interior of the housing 61 may carry a rubber lining sleeve 'F5 so as to function as a seal. A fixed stop 16 is secured to wall I0 in position to be engaged by the arm 65' at one extreme of its movement, and the inner end of the vhousing-6l functions as a stop to be engagedv by the arm at the other extreme of itsk movement.

In Fig. 8 I show the manner in which the blades 2l are mounted on 'the `shaftilll, whic-his by means of the pin 'l0 extending through diametrically opposite holes in the shaft and being Welded at its outer end to the blade.

From the foregoing it is apparent thatrif the material being prepared in the apparatus is of a consistency which would pass too freely through orices 56 to enable an effective plug seal" to be maintained in the vacuum chamber, the rate of 'A extrusion of the material through orifices 50 may be regulated by turning Ythe shaft 'HlA to rotate the disc 52 until the orifices 551are out-of coaxial register with orifices 50.

It is also apparent that, by virtuei of the novel means which I employ to maintain an effective seal for the vacuum chamber, itY is'possible to utilize a single shaft with its carried blades and screws and thus provide .a more compact and efcient apparatus.

I claim: Y

1. In apparatus for preparing plastic materials for molding, the combination ofy a casing for receiving the material, ,wallsdefining a vacuum chamber, the first of said wallsY formingY an end wall for said casing, adischarge outlet opening through an opposite wall of said chamber, a shaft extending longitudinally of said casing and chamber and into said outlet opening, said shaft being journalle'd for rotation in said rst wall, comminuting elements on said shaft pitched to move said material-toward said opening; said first wall `having extrusion apertures therethrough, and means cooperating with said apertures to open andclose 'the same, said means comprising a disc mounted to rotate against said first wall and having apertures positioned to be moved into and out of register with the apertures in the first wall in response to rotation of said disc.

2. In apparatus for preparing plastic materials for molding, the combination of a casing for receiving ,the material, walls deninga vacuum chamber, the rstof said vwalls forming an end wall for said casing, a discharge outlet opening through an opposite wall of said chamber, a shaft extending longitudinally of said casing and chamber and into said outlet opening, said shaft being journalled for rotation in said first wall, comminuting elements on said shaft pitched to move said material toward said opening; said .first wall having extrusion apertures therethrough, and means cooperating with said apertures to open and close the same, and means comprising a disc mounted to rotate against said first wall coaxial with and relative to said shaft and having apertures positioned to be moved into and out of register with the apertures in theV first wall in response to rotation of said disc.

3. The apparatus of claim l wherein there is a coaxial extrusion nozzle mounted in communication with said discharge outlet opening.

4. In apparatus for preparing plastic materials for molding, the combination of a casing for receiving the material, walls defining a vacuum chamber, the rst of said walls forming an end Wall for said casing, a vdischarge outlet opening through an opposite Wall of said chamber, a shaft extending longitudinally of said casing and chamber and into said outlet opening, said shaft being journalled for rotation insaid first wall, comminuting elements on said shaft pitched to move said material toward'said opening; said first wall having extrusion apertures therethrough, means cooperating with said apertures to open and close the same comprising a disc mounted to rotate against said first wall coaxially with and relative to said shaft and having apertures positioned to be moved into and out of register with the apertures inthe first wall in response to rotation of said disc and means Vfor rotatably securing said disc against said first Wall comprising a ring secured to said first wall.

CLIFFORD O. FIEDLER.

REFERENCES CTED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name VDate 124,431 Fuller Mar. 12, 1872 1,478,842 Staley Dec. 25, 1923 1,964,266 McElroy et al June 26, 1934 2,186,331 Flood et al Jan. 9, 1940 

